/src/openssl/providers/implementations/kdfs/scrypt.c

Source (jump to first uncovered line)
/*
 * Copyright 2017-2025 The OpenSSL Project Authors. All Rights Reserved.
 *
 * Licensed under the Apache License 2.0 (the "License").  You may not use
 * this file except in compliance with the License.  You can obtain a copy
 * in the file LICENSE in the source distribution or at
 * https://www.openssl.org/source/license.html
 */

#include <stdlib.h>
#include <stdarg.h>
#include <string.h>
#include <openssl/evp.h>
#include <openssl/kdf.h>
#include <openssl/err.h>
#include <openssl/core_names.h>
#include <openssl/proverr.h>
#include "crypto/evp.h"
#include "internal/numbers.h"
#include "prov/implementations.h"
#include "prov/provider_ctx.h"
#include "prov/providercommon.h"
#include "prov/provider_util.h"

#ifndef OPENSSL_NO_SCRYPT

static OSSL_FUNC_kdf_newctx_fn kdf_scrypt_new;
static OSSL_FUNC_kdf_dupctx_fn kdf_scrypt_dup;
static OSSL_FUNC_kdf_freectx_fn kdf_scrypt_free;
static OSSL_FUNC_kdf_reset_fn kdf_scrypt_reset;
static OSSL_FUNC_kdf_derive_fn kdf_scrypt_derive;
static OSSL_FUNC_kdf_settable_ctx_params_fn kdf_scrypt_settable_ctx_params;
static OSSL_FUNC_kdf_set_ctx_params_fn kdf_scrypt_set_ctx_params;
static OSSL_FUNC_kdf_gettable_ctx_params_fn kdf_scrypt_gettable_ctx_params;
static OSSL_FUNC_kdf_get_ctx_params_fn kdf_scrypt_get_ctx_params;

static int scrypt_alg(const char *pass, size_t passlen,
                      const unsigned char *salt, size_t saltlen,
                      uint64_t N, uint64_t r, uint64_t p, uint64_t maxmem,
                      unsigned char *key, size_t keylen, EVP_MD *sha256,
                      OSSL_LIB_CTX *libctx, const char *propq);

typedef struct {
    OSSL_LIB_CTX *libctx;
    char *propq;
    unsigned char *pass;
    size_t pass_len;
    unsigned char *salt;
    size_t salt_len;
    uint64_t N;
    uint64_t r, p;
    uint64_t maxmem_bytes;
    EVP_MD *sha256;
} KDF_SCRYPT;

static void kdf_scrypt_init(KDF_SCRYPT *ctx);

static void *kdf_scrypt_new_inner(OSSL_LIB_CTX *libctx)
{
    KDF_SCRYPT *ctx;

    if (!ossl_prov_is_running())
        return NULL;

    ctx = OPENSSL_zalloc(sizeof(*ctx));
    if (ctx == NULL)
        return NULL;
    ctx->libctx = libctx;
    kdf_scrypt_init(ctx);
    return ctx;
}

static void *kdf_scrypt_new(void *provctx)
{
    return kdf_scrypt_new_inner(PROV_LIBCTX_OF(provctx));
}

static void kdf_scrypt_free(void *vctx)
{
    KDF_SCRYPT *ctx = (KDF_SCRYPT *)vctx;

    if (ctx != NULL) {
        OPENSSL_free(ctx->propq);
        EVP_MD_free(ctx->sha256);
        kdf_scrypt_reset(ctx);
        OPENSSL_free(ctx);
    }
}

static void kdf_scrypt_reset(void *vctx)
{
    KDF_SCRYPT *ctx = (KDF_SCRYPT *)vctx;

    OPENSSL_free(ctx->salt);
    ctx->salt = NULL;
    OPENSSL_clear_free(ctx->pass, ctx->pass_len);
    ctx->pass = NULL;
    kdf_scrypt_init(ctx);
}

static void *kdf_scrypt_dup(void *vctx)
{
    const KDF_SCRYPT *src = (const KDF_SCRYPT *)vctx;
    KDF_SCRYPT *dest;

    dest = kdf_scrypt_new_inner(src->libctx);
    if (dest != NULL) {
        if (src->sha256 != NULL && !EVP_MD_up_ref(src->sha256))
            goto err;
        if (src->propq != NULL) {
            dest->propq = OPENSSL_strdup(src->propq);
            if (dest->propq == NULL)
                goto err;
        }
        if (!ossl_prov_memdup(src->salt, src->salt_len,
                              &dest->salt, &dest->salt_len)
                || !ossl_prov_memdup(src->pass, src->pass_len,
                                     &dest->pass , &dest->pass_len))
            goto err;
        dest->N = src->N;
        dest->r = src->r;
        dest->p = src->p;
        dest->maxmem_bytes = src->maxmem_bytes;
        dest->sha256 = src->sha256;
    }
    return dest;

 err:
    kdf_scrypt_free(dest);
    return NULL;
}

static void kdf_scrypt_init(KDF_SCRYPT *ctx)
{
    /* Default values are the most conservative recommendation given in the
     * original paper of C. Percival. Derivation uses roughly 1 GiB of memory
     * for this parameter choice (approx. 128 * r * N * p bytes).
     */
    ctx->N = 1 << 20;
    ctx->r = 8;
    ctx->p = 1;
    ctx->maxmem_bytes = 1025 * 1024 * 1024;
}

static int scrypt_set_membuf(unsigned char **buffer, size_t *buflen,
                             const OSSL_PARAM *p)
{
    OPENSSL_clear_free(*buffer, *buflen);
    *buffer = NULL;
    *buflen = 0;

    if (p->data_size == 0) {
        if ((*buffer = OPENSSL_malloc(1)) == NULL)
            return 0;
    } else if (p->data != NULL) {
        if (!OSSL_PARAM_get_octet_string(p, (void **)buffer, 0, buflen))
            return 0;
    }
    return 1;
}

static int set_digest(KDF_SCRYPT *ctx)
{
    EVP_MD_free(ctx->sha256);
    ctx->sha256 = EVP_MD_fetch(ctx->libctx, "sha256", ctx->propq);
    if (ctx->sha256 == NULL) {
        ERR_raise(ERR_LIB_PROV, PROV_R_UNABLE_TO_LOAD_SHA256);
        return 0;
    }
    return 1;
}

static int set_property_query(KDF_SCRYPT *ctx, const char *propq)
{
    OPENSSL_free(ctx->propq);
    ctx->propq = NULL;
    if (propq != NULL) {
        ctx->propq = OPENSSL_strdup(propq);
        if (ctx->propq == NULL)
            return 0;
    }
    return 1;
}

static int kdf_scrypt_derive(void *vctx, unsigned char *key, size_t keylen,
                             const OSSL_PARAM params[])
{
    KDF_SCRYPT *ctx = (KDF_SCRYPT *)vctx;

    if (!ossl_prov_is_running() || !kdf_scrypt_set_ctx_params(ctx, params))
        return 0;

    if (ctx->pass == NULL) {
        ERR_raise(ERR_LIB_PROV, PROV_R_MISSING_PASS);
        return 0;
    }

    if (ctx->salt == NULL) {
        ERR_raise(ERR_LIB_PROV, PROV_R_MISSING_SALT);
        return 0;
    }

    if (ctx->sha256 == NULL && !set_digest(ctx))
        return 0;

    return scrypt_alg((char *)ctx->pass, ctx->pass_len, ctx->salt,
                      ctx->salt_len, ctx->N, ctx->r, ctx->p,
                      ctx->maxmem_bytes, key, keylen, ctx->sha256,
                      ctx->libctx, ctx->propq);
}

static int is_power_of_two(uint64_t value)
{
    return (value != 0) && ((value & (value - 1)) == 0);
}

static int kdf_scrypt_set_ctx_params(void *vctx, const OSSL_PARAM params[])
{
    const OSSL_PARAM *p;
    KDF_SCRYPT *ctx = vctx;
    uint64_t u64_value;

    if (ossl_param_is_empty(params))
        return 1;

    if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_PASSWORD)) != NULL)
        if (!scrypt_set_membuf(&ctx->pass, &ctx->pass_len, p))
            return 0;

    if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_SALT)) != NULL)
        if (!scrypt_set_membuf(&ctx->salt, &ctx->salt_len, p))
            return 0;

    if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_SCRYPT_N))
        != NULL) {
        if (!OSSL_PARAM_get_uint64(p, &u64_value)
            || u64_value <= 1
            || !is_power_of_two(u64_value))
            return 0;
        ctx->N = u64_value;
    }

    if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_SCRYPT_R))
        != NULL) {
        if (!OSSL_PARAM_get_uint64(p, &u64_value) || u64_value < 1)
            return 0;
        ctx->r = u64_value;
    }

    if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_SCRYPT_P))
        != NULL) {
        if (!OSSL_PARAM_get_uint64(p, &u64_value) || u64_value < 1)
            return 0;
        ctx->p = u64_value;
    }

    if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_SCRYPT_MAXMEM))
        != NULL) {
        if (!OSSL_PARAM_get_uint64(p, &u64_value) || u64_value < 1)
            return 0;
        ctx->maxmem_bytes = u64_value;
    }

    p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_PROPERTIES);
    if (p != NULL) {
        if (p->data_type != OSSL_PARAM_UTF8_STRING
            || !set_property_query(ctx, p->data)
            || !set_digest(ctx))
            return 0;
    }
    return 1;
}

static const OSSL_PARAM *kdf_scrypt_settable_ctx_params(ossl_unused void *ctx,
                                                        ossl_unused void *p_ctx)
{
    static const OSSL_PARAM known_settable_ctx_params[] = {
        OSSL_PARAM_octet_string(OSSL_KDF_PARAM_PASSWORD, NULL, 0),
        OSSL_PARAM_octet_string(OSSL_KDF_PARAM_SALT, NULL, 0),
        OSSL_PARAM_uint64(OSSL_KDF_PARAM_SCRYPT_N, NULL),
        OSSL_PARAM_uint32(OSSL_KDF_PARAM_SCRYPT_R, NULL),
        OSSL_PARAM_uint32(OSSL_KDF_PARAM_SCRYPT_P, NULL),
        OSSL_PARAM_uint64(OSSL_KDF_PARAM_SCRYPT_MAXMEM, NULL),
        OSSL_PARAM_utf8_string(OSSL_KDF_PARAM_PROPERTIES, NULL, 0),
        OSSL_PARAM_END
    };
    return known_settable_ctx_params;
}

static int kdf_scrypt_get_ctx_params(void *vctx, OSSL_PARAM params[])
{
    OSSL_PARAM *p;

    if ((p = OSSL_PARAM_locate(params, OSSL_KDF_PARAM_SIZE)) != NULL)
        return OSSL_PARAM_set_size_t(p, SIZE_MAX);
    return -2;
}

static const OSSL_PARAM *kdf_scrypt_gettable_ctx_params(ossl_unused void *ctx,
                                                        ossl_unused void *p_ctx)
{
    static const OSSL_PARAM known_gettable_ctx_params[] = {
        OSSL_PARAM_size_t(OSSL_KDF_PARAM_SIZE, NULL),
        OSSL_PARAM_END
    };
    return known_gettable_ctx_params;
}

const OSSL_DISPATCH ossl_kdf_scrypt_functions[] = {
    { OSSL_FUNC_KDF_NEWCTX, (void(*)(void))kdf_scrypt_new },
    { OSSL_FUNC_KDF_DUPCTX, (void(*)(void))kdf_scrypt_dup },
    { OSSL_FUNC_KDF_FREECTX, (void(*)(void))kdf_scrypt_free },
    { OSSL_FUNC_KDF_RESET, (void(*)(void))kdf_scrypt_reset },
    { OSSL_FUNC_KDF_DERIVE, (void(*)(void))kdf_scrypt_derive },
    { OSSL_FUNC_KDF_SETTABLE_CTX_PARAMS,
      (void(*)(void))kdf_scrypt_settable_ctx_params },
    { OSSL_FUNC_KDF_SET_CTX_PARAMS, (void(*)(void))kdf_scrypt_set_ctx_params },
    { OSSL_FUNC_KDF_GETTABLE_CTX_PARAMS,
      (void(*)(void))kdf_scrypt_gettable_ctx_params },
    { OSSL_FUNC_KDF_GET_CTX_PARAMS, (void(*)(void))kdf_scrypt_get_ctx_params },
    OSSL_DISPATCH_END
};

#define R(a,b) (((a) << (b)) | ((a) >> (32 - (b))))
static void salsa208_word_specification(uint32_t inout[16])
{
    int i;
    uint32_t x[16];

    memcpy(x, inout, sizeof(x));
    for (i = 8; i > 0; i -= 2) {
        x[4] ^= R(x[0] + x[12], 7);
        x[8] ^= R(x[4] + x[0], 9);
        x[12] ^= R(x[8] + x[4], 13);
        x[0] ^= R(x[12] + x[8], 18);
        x[9] ^= R(x[5] + x[1], 7);
        x[13] ^= R(x[9] + x[5], 9);
        x[1] ^= R(x[13] + x[9], 13);
        x[5] ^= R(x[1] + x[13], 18);
        x[14] ^= R(x[10] + x[6], 7);
        x[2] ^= R(x[14] + x[10], 9);
        x[6] ^= R(x[2] + x[14], 13);
        x[10] ^= R(x[6] + x[2], 18);
        x[3] ^= R(x[15] + x[11], 7);
        x[7] ^= R(x[3] + x[15], 9);
        x[11] ^= R(x[7] + x[3], 13);
        x[15] ^= R(x[11] + x[7], 18);
        x[1] ^= R(x[0] + x[3], 7);
        x[2] ^= R(x[1] + x[0], 9);
        x[3] ^= R(x[2] + x[1], 13);
        x[0] ^= R(x[3] + x[2], 18);
        x[6] ^= R(x[5] + x[4], 7);
        x[7] ^= R(x[6] + x[5], 9);
        x[4] ^= R(x[7] + x[6], 13);
        x[5] ^= R(x[4] + x[7], 18);
        x[11] ^= R(x[10] + x[9], 7);
        x[8] ^= R(x[11] + x[10], 9);
        x[9] ^= R(x[8] + x[11], 13);
        x[10] ^= R(x[9] + x[8], 18);
        x[12] ^= R(x[15] + x[14], 7);
        x[13] ^= R(x[12] + x[15], 9);
        x[14] ^= R(x[13] + x[12], 13);
        x[15] ^= R(x[14] + x[13], 18);
    }
    for (i = 0; i < 16; ++i)
        inout[i] += x[i];
    OPENSSL_cleanse(x, sizeof(x));
}

static void scryptBlockMix(uint32_t *B_, uint32_t *B, uint64_t r)
{
    uint64_t i, j;
    uint32_t X[16], *pB;

    memcpy(X, B + (r * 2 - 1) * 16, sizeof(X));
    pB = B;
    for (i = 0; i < r * 2; i++) {
        for (j = 0; j < 16; j++)
            X[j] ^= *pB++;
        salsa208_word_specification(X);
        memcpy(B_ + (i / 2 + (i & 1) * r) * 16, X, sizeof(X));
    }
    OPENSSL_cleanse(X, sizeof(X));
}

static void scryptROMix(unsigned char *B, uint64_t r, uint64_t N,
                        uint32_t *X, uint32_t *T, uint32_t *V)
{
    unsigned char *pB;
    uint32_t *pV;
    uint64_t i, k;

    /* Convert from little endian input */
    for (pV = V, i = 0, pB = B; i < 32 * r; i++, pV++) {
        *pV = *pB++;
        *pV |= *pB++ << 8;
        *pV |= *pB++ << 16;
        *pV |= (uint32_t)*pB++ << 24;
    }

    for (i = 1; i < N; i++, pV += 32 * r)
        scryptBlockMix(pV, pV - 32 * r, r);

    scryptBlockMix(X, V + (N - 1) * 32 * r, r);

    for (i = 0; i < N; i++) {
        uint32_t j;
        j = X[16 * (2 * r - 1)] % N;
        pV = V + 32 * r * j;
        for (k = 0; k < 32 * r; k++)
            T[k] = X[k] ^ *pV++;
        scryptBlockMix(X, T, r);
    }
    /* Convert output to little endian */
    for (i = 0, pB = B; i < 32 * r; i++) {
        uint32_t xtmp = X[i];
        *pB++ = xtmp & 0xff;
        *pB++ = (xtmp >> 8) & 0xff;
        *pB++ = (xtmp >> 16) & 0xff;
        *pB++ = (xtmp >> 24) & 0xff;
    }
}

#ifndef SIZE_MAX
# define SIZE_MAX    ((size_t)-1)
#endif

/*
 * Maximum power of two that will fit in uint64_t: this should work on
 * most (all?) platforms.
 */

#define LOG2_UINT64_MAX         (sizeof(uint64_t) * 8 - 1)

/*
 * Maximum value of p * r:
 * p <= ((2^32-1) * hLen) / MFLen =>
 * p <= ((2^32-1) * 32) / (128 * r) =>
 * p * r <= (2^30-1)
 */

#define SCRYPT_PR_MAX   ((1 << 30) - 1)

static int scrypt_alg(const char *pass, size_t passlen,
                      const unsigned char *salt, size_t saltlen,
                      uint64_t N, uint64_t r, uint64_t p, uint64_t maxmem,
                      unsigned char *key, size_t keylen, EVP_MD *sha256,
                      OSSL_LIB_CTX *libctx, const char *propq)
{
    int rv = 0;
    unsigned char *B;
    uint32_t *X, *V, *T;
    uint64_t i, Blen, Vlen;

    /* Sanity check parameters */
    /* initial check, r,p must be non zero, N >= 2 and a power of 2 */
    if (r == 0 || p == 0 || N < 2 || (N & (N - 1)))
        return 0;
    /* Check p * r < SCRYPT_PR_MAX avoiding overflow */
    if (p > SCRYPT_PR_MAX / r) {
        ERR_raise(ERR_LIB_EVP, EVP_R_MEMORY_LIMIT_EXCEEDED);
        return 0;
    }

    /*
     * Need to check N: if 2^(128 * r / 8) overflows limit this is
     * automatically satisfied since N <= UINT64_MAX.
     */

    if (16 * r <= LOG2_UINT64_MAX) {
        if (N >= (((uint64_t)1) << (16 * r))) {
            ERR_raise(ERR_LIB_EVP, EVP_R_MEMORY_LIMIT_EXCEEDED);
            return 0;
        }
    }

    /* Memory checks: check total allocated buffer size fits in uint64_t */

    /*
     * B size in section 5 step 1.S
     * Note: we know p * 128 * r < UINT64_MAX because we already checked
     * p * r < SCRYPT_PR_MAX
     */
    Blen = p * 128 * r;
    /*
     * Yet we pass it as integer to PKCS5_PBKDF2_HMAC... [This would
     * have to be revised when/if PKCS5_PBKDF2_HMAC accepts size_t.]
     */
    if (Blen > INT_MAX) {
        ERR_raise(ERR_LIB_EVP, EVP_R_MEMORY_LIMIT_EXCEEDED);
        return 0;
    }

    /*
     * Check 32 * r * (N + 2) * sizeof(uint32_t) fits in uint64_t
     * This is combined size V, X and T (section 4)
     */
    i = UINT64_MAX / (32 * sizeof(uint32_t));
    if (N + 2 > i / r) {
        ERR_raise(ERR_LIB_EVP, EVP_R_MEMORY_LIMIT_EXCEEDED);
        return 0;
    }
    Vlen = 32 * r * (N + 2) * sizeof(uint32_t);

    /* check total allocated size fits in uint64_t */
    if (Blen > UINT64_MAX - Vlen) {
        ERR_raise(ERR_LIB_EVP, EVP_R_MEMORY_LIMIT_EXCEEDED);
        return 0;
    }

    /* Check that the maximum memory doesn't exceed a size_t limits */
    if (maxmem > SIZE_MAX)
        maxmem = SIZE_MAX;

    if (Blen + Vlen > maxmem) {
        ERR_raise(ERR_LIB_EVP, EVP_R_MEMORY_LIMIT_EXCEEDED);
        return 0;
    }

    /* If no key return to indicate parameters are OK */
    if (key == NULL)
        return 1;

    B = OPENSSL_malloc((size_t)(Blen + Vlen));
    if (B == NULL)
        return 0;
    X = (uint32_t *)(B + Blen);
    T = X + 32 * r;
    V = T + 32 * r;
    if (ossl_pkcs5_pbkdf2_hmac_ex(pass, passlen, salt, saltlen, 1, sha256,
                                  (int)Blen, B, libctx, propq) == 0)
        goto err;

    for (i = 0; i < p; i++)
        scryptROMix(B + 128 * r * i, r, N, X, T, V);

    if (ossl_pkcs5_pbkdf2_hmac_ex(pass, passlen, B, (int)Blen, 1, sha256,
                                  keylen, key, libctx, propq) == 0)
        goto err;
    rv = 1;
 err:
    if (rv == 0)
        ERR_raise(ERR_LIB_EVP, EVP_R_PBKDF2_ERROR);

    OPENSSL_clear_free(B, (size_t)(Blen + Vlen));
    return rv;
}

#endif

Coverage Report

Created: 2025-06-13 06:57

Line	Count	Source (jump to first uncovered line)
1		/*
2		* Copyright 2017-2025 The OpenSSL Project Authors. All Rights Reserved.
3		*
4		* Licensed under the Apache License 2.0 (the "License"). You may not use
5		* this file except in compliance with the License. You can obtain a copy
6		* in the file LICENSE in the source distribution or at
7		* https://www.openssl.org/source/license.html
8		*/
9
10		#include <stdlib.h>
11		#include <stdarg.h>
12		#include <string.h>
13		#include <openssl/evp.h>
14		#include <openssl/kdf.h>
15		#include <openssl/err.h>
16		#include <openssl/core_names.h>
17		#include <openssl/proverr.h>
18		#include "crypto/evp.h"
19		#include "internal/numbers.h"
20		#include "prov/implementations.h"
21		#include "prov/provider_ctx.h"
22		#include "prov/providercommon.h"
23		#include "prov/provider_util.h"
24
25		#ifndef OPENSSL_NO_SCRYPT
26
27		static OSSL_FUNC_kdf_newctx_fn kdf_scrypt_new;
28		static OSSL_FUNC_kdf_dupctx_fn kdf_scrypt_dup;
29		static OSSL_FUNC_kdf_freectx_fn kdf_scrypt_free;
30		static OSSL_FUNC_kdf_reset_fn kdf_scrypt_reset;
31		static OSSL_FUNC_kdf_derive_fn kdf_scrypt_derive;
32		static OSSL_FUNC_kdf_settable_ctx_params_fn kdf_scrypt_settable_ctx_params;
33		static OSSL_FUNC_kdf_set_ctx_params_fn kdf_scrypt_set_ctx_params;
34		static OSSL_FUNC_kdf_gettable_ctx_params_fn kdf_scrypt_gettable_ctx_params;
35		static OSSL_FUNC_kdf_get_ctx_params_fn kdf_scrypt_get_ctx_params;
36
37		static int scrypt_alg(const char *pass, size_t passlen,
38		const unsigned char *salt, size_t saltlen,
39		uint64_t N, uint64_t r, uint64_t p, uint64_t maxmem,
40		unsigned char key, size_t keylen, EVP_MD sha256,
41		OSSL_LIB_CTX libctx, const char propq);
42
43		typedef struct {
44		OSSL_LIB_CTX *libctx;
45		char *propq;
46		unsigned char *pass;
47		size_t pass_len;
48		unsigned char *salt;
49		size_t salt_len;
50		uint64_t N;
51		uint64_t r, p;
52		uint64_t maxmem_bytes;
53		EVP_MD *sha256;
54		} KDF_SCRYPT;
55
56		static void kdf_scrypt_init(KDF_SCRYPT *ctx);
57
58		static void kdf_scrypt_new_inner(OSSL_LIB_CTX libctx)
59	0	{
60	0	KDF_SCRYPT *ctx;
61
62	0	if (!ossl_prov_is_running())
63	0	return NULL;
64
65	0	ctx = OPENSSL_zalloc(sizeof(*ctx));
66	0	if (ctx == NULL)
67	0	return NULL;
68	0	ctx->libctx = libctx;
69	0	kdf_scrypt_init(ctx);
70	0	return ctx;
71	0	}
72
73		static void kdf_scrypt_new(void provctx)
74	0	{
75	0	return kdf_scrypt_new_inner(PROV_LIBCTX_OF(provctx));
76	0	}
77
78		static void kdf_scrypt_free(void *vctx)
79	0	{
80	0	KDF_SCRYPT ctx = (KDF_SCRYPT )vctx;
81
82	0	if (ctx != NULL) {
83	0	OPENSSL_free(ctx->propq);
84	0	EVP_MD_free(ctx->sha256);
85	0	kdf_scrypt_reset(ctx);
86	0	OPENSSL_free(ctx);
87	0	}
88	0	}
89
90		static void kdf_scrypt_reset(void *vctx)
91	0	{
92	0	KDF_SCRYPT ctx = (KDF_SCRYPT )vctx;
93
94	0	OPENSSL_free(ctx->salt);
95	0	ctx->salt = NULL;
96	0	OPENSSL_clear_free(ctx->pass, ctx->pass_len);
97	0	ctx->pass = NULL;
98	0	kdf_scrypt_init(ctx);
99	0	}
100
101		static void kdf_scrypt_dup(void vctx)
102	0	{
103	0	const KDF_SCRYPT src = (const KDF_SCRYPT )vctx;
104	0	KDF_SCRYPT *dest;
105
106	0	dest = kdf_scrypt_new_inner(src->libctx);
107	0	if (dest != NULL) {
108	0	if (src->sha256 != NULL && !EVP_MD_up_ref(src->sha256))
109	0	goto err;
110	0	if (src->propq != NULL) {
111	0	dest->propq = OPENSSL_strdup(src->propq);
112	0	if (dest->propq == NULL)
113	0	goto err;
114	0	}
115	0	if (!ossl_prov_memdup(src->salt, src->salt_len,
116	0	&dest->salt, &dest->salt_len)
117	0	\|\| !ossl_prov_memdup(src->pass, src->pass_len,
118	0	&dest->pass , &dest->pass_len))
119	0	goto err;
120	0	dest->N = src->N;
121	0	dest->r = src->r;
122	0	dest->p = src->p;
123	0	dest->maxmem_bytes = src->maxmem_bytes;
124	0	dest->sha256 = src->sha256;
125	0	}
126	0	return dest;
127
128	0	err:
129	0	kdf_scrypt_free(dest);
130	0	return NULL;
131	0	}
132
133		static void kdf_scrypt_init(KDF_SCRYPT *ctx)
134	0	{
135		/* Default values are the most conservative recommendation given in the
136		* original paper of C. Percival. Derivation uses roughly 1 GiB of memory
137		* for this parameter choice (approx. 128 * r * N * p bytes).
138		*/
139	0	ctx->N = 1 << 20;
140	0	ctx->r = 8;
141	0	ctx->p = 1;
142	0	ctx->maxmem_bytes = 1025 * 1024 * 1024;
143	0	}
144
145		static int scrypt_set_membuf(unsigned char *buffer, size_t buflen,
146		const OSSL_PARAM *p)
147	0	{
148	0	OPENSSL_clear_free(buffer, buflen);
149	0	*buffer = NULL;
150	0	*buflen = 0;
151
152	0	if (p->data_size == 0) {
153	0	if ((*buffer = OPENSSL_malloc(1)) == NULL)
154	0	return 0;
155	0	} else if (p->data != NULL) {
156	0	if (!OSSL_PARAM_get_octet_string(p, (void **)buffer, 0, buflen))
157	0	return 0;
158	0	}
159	0	return 1;
160	0	}
161
162		static int set_digest(KDF_SCRYPT *ctx)
163	0	{
164	0	EVP_MD_free(ctx->sha256);
165	0	ctx->sha256 = EVP_MD_fetch(ctx->libctx, "sha256", ctx->propq);
166	0	if (ctx->sha256 == NULL) {
167	0	ERR_raise(ERR_LIB_PROV, PROV_R_UNABLE_TO_LOAD_SHA256);
168	0	return 0;
169	0	}
170	0	return 1;
171	0	}
172
173		static int set_property_query(KDF_SCRYPT ctx, const char propq)
174	0	{
175	0	OPENSSL_free(ctx->propq);
176	0	ctx->propq = NULL;
177	0	if (propq != NULL) {
178	0	ctx->propq = OPENSSL_strdup(propq);
179	0	if (ctx->propq == NULL)
180	0	return 0;
181	0	}
182	0	return 1;
183	0	}
184
185		static int kdf_scrypt_derive(void vctx, unsigned char key, size_t keylen,
186		const OSSL_PARAM params[])
187	0	{
188	0	KDF_SCRYPT ctx = (KDF_SCRYPT )vctx;
189
190	0	if (!ossl_prov_is_running() \|\| !kdf_scrypt_set_ctx_params(ctx, params))
191	0	return 0;
192
193	0	if (ctx->pass == NULL) {
194	0	ERR_raise(ERR_LIB_PROV, PROV_R_MISSING_PASS);
195	0	return 0;
196	0	}
197
198	0	if (ctx->salt == NULL) {
199	0	ERR_raise(ERR_LIB_PROV, PROV_R_MISSING_SALT);
200	0	return 0;
201	0	}
202
203	0	if (ctx->sha256 == NULL && !set_digest(ctx))
204	0	return 0;
205
206	0	return scrypt_alg((char *)ctx->pass, ctx->pass_len, ctx->salt,
207	0	ctx->salt_len, ctx->N, ctx->r, ctx->p,
208	0	ctx->maxmem_bytes, key, keylen, ctx->sha256,
209	0	ctx->libctx, ctx->propq);
210	0	}
211
212		static int is_power_of_two(uint64_t value)
213	0	{
214	0	return (value != 0) && ((value & (value - 1)) == 0);
215	0	}
216
217		static int kdf_scrypt_set_ctx_params(void *vctx, const OSSL_PARAM params[])
218	0	{
219	0	const OSSL_PARAM *p;
220	0	KDF_SCRYPT *ctx = vctx;
221	0	uint64_t u64_value;
222
223	0	if (ossl_param_is_empty(params))
224	0	return 1;
225
226	0	if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_PASSWORD)) != NULL)
227	0	if (!scrypt_set_membuf(&ctx->pass, &ctx->pass_len, p))
228	0	return 0;
229
230	0	if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_SALT)) != NULL)
231	0	if (!scrypt_set_membuf(&ctx->salt, &ctx->salt_len, p))
232	0	return 0;
233
234	0	if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_SCRYPT_N))
235	0	!= NULL) {
236	0	if (!OSSL_PARAM_get_uint64(p, &u64_value)
237	0	\|\| u64_value <= 1
238	0	\|\| !is_power_of_two(u64_value))
239	0	return 0;
240	0	ctx->N = u64_value;
241	0	}
242
243	0	if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_SCRYPT_R))
244	0	!= NULL) {
245	0	if (!OSSL_PARAM_get_uint64(p, &u64_value) \|\| u64_value < 1)
246	0	return 0;
247	0	ctx->r = u64_value;
248	0	}
249
250	0	if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_SCRYPT_P))
251	0	!= NULL) {
252	0	if (!OSSL_PARAM_get_uint64(p, &u64_value) \|\| u64_value < 1)
253	0	return 0;
254	0	ctx->p = u64_value;
255	0	}
256
257	0	if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_SCRYPT_MAXMEM))
258	0	!= NULL) {
259	0	if (!OSSL_PARAM_get_uint64(p, &u64_value) \|\| u64_value < 1)
260	0	return 0;
261	0	ctx->maxmem_bytes = u64_value;
262	0	}
263
264	0	p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_PROPERTIES);
265	0	if (p != NULL) {
266	0	if (p->data_type != OSSL_PARAM_UTF8_STRING
267	0	\|\| !set_property_query(ctx, p->data)
268	0	\|\| !set_digest(ctx))
269	0	return 0;
270	0	}
271	0	return 1;
272	0	}
273
274		static const OSSL_PARAM kdf_scrypt_settable_ctx_params(ossl_unused void ctx,
275		ossl_unused void *p_ctx)
276	0	{
277	0	static const OSSL_PARAM known_settable_ctx_params[] = {
278	0	OSSL_PARAM_octet_string(OSSL_KDF_PARAM_PASSWORD, NULL, 0),
279	0	OSSL_PARAM_octet_string(OSSL_KDF_PARAM_SALT, NULL, 0),
280	0	OSSL_PARAM_uint64(OSSL_KDF_PARAM_SCRYPT_N, NULL),
281	0	OSSL_PARAM_uint32(OSSL_KDF_PARAM_SCRYPT_R, NULL),
282	0	OSSL_PARAM_uint32(OSSL_KDF_PARAM_SCRYPT_P, NULL),
283	0	OSSL_PARAM_uint64(OSSL_KDF_PARAM_SCRYPT_MAXMEM, NULL),
284	0	OSSL_PARAM_utf8_string(OSSL_KDF_PARAM_PROPERTIES, NULL, 0),
285	0	OSSL_PARAM_END
286	0	};
287	0	return known_settable_ctx_params;
288	0	}
289
290		static int kdf_scrypt_get_ctx_params(void *vctx, OSSL_PARAM params[])
291	0	{
292	0	OSSL_PARAM *p;
293
294	0	if ((p = OSSL_PARAM_locate(params, OSSL_KDF_PARAM_SIZE)) != NULL)
295	0	return OSSL_PARAM_set_size_t(p, SIZE_MAX);
296	0	return -2;
297	0	}
298
299		static const OSSL_PARAM kdf_scrypt_gettable_ctx_params(ossl_unused void ctx,
300		ossl_unused void *p_ctx)
301	0	{
302	0	static const OSSL_PARAM known_gettable_ctx_params[] = {
303	0	OSSL_PARAM_size_t(OSSL_KDF_PARAM_SIZE, NULL),
304	0	OSSL_PARAM_END
305	0	};
306	0	return known_gettable_ctx_params;
307	0	}
308
309		const OSSL_DISPATCH ossl_kdf_scrypt_functions[] = {
310		{ OSSL_FUNC_KDF_NEWCTX, (void(*)(void))kdf_scrypt_new },
311		{ OSSL_FUNC_KDF_DUPCTX, (void(*)(void))kdf_scrypt_dup },
312		{ OSSL_FUNC_KDF_FREECTX, (void(*)(void))kdf_scrypt_free },
313		{ OSSL_FUNC_KDF_RESET, (void(*)(void))kdf_scrypt_reset },
314		{ OSSL_FUNC_KDF_DERIVE, (void(*)(void))kdf_scrypt_derive },
315		{ OSSL_FUNC_KDF_SETTABLE_CTX_PARAMS,
316		(void(*)(void))kdf_scrypt_settable_ctx_params },
317		{ OSSL_FUNC_KDF_SET_CTX_PARAMS, (void(*)(void))kdf_scrypt_set_ctx_params },
318		{ OSSL_FUNC_KDF_GETTABLE_CTX_PARAMS,
319		(void(*)(void))kdf_scrypt_gettable_ctx_params },
320		{ OSSL_FUNC_KDF_GET_CTX_PARAMS, (void(*)(void))kdf_scrypt_get_ctx_params },
321		OSSL_DISPATCH_END
322		};
323
324	0	#define R(a,b) (((a) << (b)) \| ((a) >> (32 - (b))))
325		static void salsa208_word_specification(uint32_t inout[16])
326	0	{
327	0	int i;
328	0	uint32_t x[16];
329
330	0	memcpy(x, inout, sizeof(x));
331	0	for (i = 8; i > 0; i -= 2) {
332	0	x[4] ^= R(x[0] + x[12], 7);
333	0	x[8] ^= R(x[4] + x[0], 9);
334	0	x[12] ^= R(x[8] + x[4], 13);
335	0	x[0] ^= R(x[12] + x[8], 18);
336	0	x[9] ^= R(x[5] + x[1], 7);
337	0	x[13] ^= R(x[9] + x[5], 9);
338	0	x[1] ^= R(x[13] + x[9], 13);
339	0	x[5] ^= R(x[1] + x[13], 18);
340	0	x[14] ^= R(x[10] + x[6], 7);
341	0	x[2] ^= R(x[14] + x[10], 9);
342	0	x[6] ^= R(x[2] + x[14], 13);
343	0	x[10] ^= R(x[6] + x[2], 18);
344	0	x[3] ^= R(x[15] + x[11], 7);
345	0	x[7] ^= R(x[3] + x[15], 9);
346	0	x[11] ^= R(x[7] + x[3], 13);
347	0	x[15] ^= R(x[11] + x[7], 18);
348	0	x[1] ^= R(x[0] + x[3], 7);
349	0	x[2] ^= R(x[1] + x[0], 9);
350	0	x[3] ^= R(x[2] + x[1], 13);
351	0	x[0] ^= R(x[3] + x[2], 18);
352	0	x[6] ^= R(x[5] + x[4], 7);
353	0	x[7] ^= R(x[6] + x[5], 9);
354	0	x[4] ^= R(x[7] + x[6], 13);
355	0	x[5] ^= R(x[4] + x[7], 18);
356	0	x[11] ^= R(x[10] + x[9], 7);
357	0	x[8] ^= R(x[11] + x[10], 9);
358	0	x[9] ^= R(x[8] + x[11], 13);
359	0	x[10] ^= R(x[9] + x[8], 18);
360	0	x[12] ^= R(x[15] + x[14], 7);
361	0	x[13] ^= R(x[12] + x[15], 9);
362	0	x[14] ^= R(x[13] + x[12], 13);
363	0	x[15] ^= R(x[14] + x[13], 18);
364	0	}
365	0	for (i = 0; i < 16; ++i)
366	0	inout[i] += x[i];
367	0	OPENSSL_cleanse(x, sizeof(x));
368	0	}
369
370		static void scryptBlockMix(uint32_t B_, uint32_t B, uint64_t r)
371	0	{
372	0	uint64_t i, j;
373	0	uint32_t X[16], *pB;
374
375	0	memcpy(X, B + (r * 2 - 1) * 16, sizeof(X));
376	0	pB = B;
377	0	for (i = 0; i < r * 2; i++) {
378	0	for (j = 0; j < 16; j++)
379	0	X[j] ^= *pB++;
380	0	salsa208_word_specification(X);
381	0	memcpy(B_ + (i / 2 + (i & 1) * r) * 16, X, sizeof(X));
382	0	}
383	0	OPENSSL_cleanse(X, sizeof(X));
384	0	}
385
386		static void scryptROMix(unsigned char *B, uint64_t r, uint64_t N,
387		uint32_t X, uint32_t T, uint32_t *V)
388	0	{
389	0	unsigned char *pB;
390	0	uint32_t *pV;
391	0	uint64_t i, k;
392
393		/* Convert from little endian input */
394	0	for (pV = V, i = 0, pB = B; i < 32 * r; i++, pV++) {
395	0	pV = pB++;
396	0	pV \|= pB++ << 8;
397	0	pV \|= pB++ << 16;
398	0	pV \|= (uint32_t)pB++ << 24;
399	0	}
400
401	0	for (i = 1; i < N; i++, pV += 32 * r)
402	0	scryptBlockMix(pV, pV - 32 * r, r);
403
404	0	scryptBlockMix(X, V + (N - 1) * 32 * r, r);
405
406	0	for (i = 0; i < N; i++) {
407	0	uint32_t j;
408	0	j = X[16 * (2 * r - 1)] % N;
409	0	pV = V + 32 * r * j;
410	0	for (k = 0; k < 32 * r; k++)
411	0	T[k] = X[k] ^ *pV++;
412	0	scryptBlockMix(X, T, r);
413	0	}
414		/* Convert output to little endian */
415	0	for (i = 0, pB = B; i < 32 * r; i++) {
416	0	uint32_t xtmp = X[i];
417	0	*pB++ = xtmp & 0xff;
418	0	*pB++ = (xtmp >> 8) & 0xff;
419	0	*pB++ = (xtmp >> 16) & 0xff;
420	0	*pB++ = (xtmp >> 24) & 0xff;
421	0	}
422	0	}
423
424		#ifndef SIZE_MAX
425		# define SIZE_MAX ((size_t)-1)
426		#endif
427
428		/*
429		* Maximum power of two that will fit in uint64_t: this should work on
430		* most (all?) platforms.
431		*/
432
433	0	#define LOG2_UINT64_MAX (sizeof(uint64_t) * 8 - 1)
434
435		/*
436		* Maximum value of p * r:
437		* p <= ((2^32-1) * hLen) / MFLen =>
438		* p <= ((2^32-1) * 32) / (128 * r) =>
439		* p * r <= (2^30-1)
440		*/
441
442	0	#define SCRYPT_PR_MAX ((1 << 30) - 1)
443
444		static int scrypt_alg(const char *pass, size_t passlen,
445		const unsigned char *salt, size_t saltlen,
446		uint64_t N, uint64_t r, uint64_t p, uint64_t maxmem,
447		unsigned char key, size_t keylen, EVP_MD sha256,
448		OSSL_LIB_CTX libctx, const char propq)
449	0	{
450	0	int rv = 0;
451	0	unsigned char *B;
452	0	uint32_t X, V, *T;
453	0	uint64_t i, Blen, Vlen;
454
455		/* Sanity check parameters */
456		/* initial check, r,p must be non zero, N >= 2 and a power of 2 */
457	0	if (r == 0 \|\| p == 0 \|\| N < 2 \|\| (N & (N - 1)))
458	0	return 0;
459		/* Check p * r < SCRYPT_PR_MAX avoiding overflow */
460	0	if (p > SCRYPT_PR_MAX / r) {
461	0	ERR_raise(ERR_LIB_EVP, EVP_R_MEMORY_LIMIT_EXCEEDED);
462	0	return 0;
463	0	}
464
465		/*
466		* Need to check N: if 2^(128 * r / 8) overflows limit this is
467		* automatically satisfied since N <= UINT64_MAX.
468		*/
469
470	0	if (16 * r <= LOG2_UINT64_MAX) {
471	0	if (N >= (((uint64_t)1) << (16 * r))) {
472	0	ERR_raise(ERR_LIB_EVP, EVP_R_MEMORY_LIMIT_EXCEEDED);
473	0	return 0;
474	0	}
475	0	}
476
477		/* Memory checks: check total allocated buffer size fits in uint64_t */
478
479		/*
480		* B size in section 5 step 1.S
481		* Note: we know p * 128 * r < UINT64_MAX because we already checked
482		* p * r < SCRYPT_PR_MAX
483		*/
484	0	Blen = p * 128 * r;
485		/*
486		* Yet we pass it as integer to PKCS5_PBKDF2_HMAC... [This would
487		* have to be revised when/if PKCS5_PBKDF2_HMAC accepts size_t.]
488		*/
489	0	if (Blen > INT_MAX) {
490	0	ERR_raise(ERR_LIB_EVP, EVP_R_MEMORY_LIMIT_EXCEEDED);
491	0	return 0;
492	0	}
493
494		/*
495		* Check 32 * r * (N + 2) * sizeof(uint32_t) fits in uint64_t
496		* This is combined size V, X and T (section 4)
497		*/
498	0	i = UINT64_MAX / (32 * sizeof(uint32_t));
499	0	if (N + 2 > i / r) {
500	0	ERR_raise(ERR_LIB_EVP, EVP_R_MEMORY_LIMIT_EXCEEDED);
501	0	return 0;
502	0	}
503	0	Vlen = 32 * r * (N + 2) * sizeof(uint32_t);
504
505		/* check total allocated size fits in uint64_t */
506	0	if (Blen > UINT64_MAX - Vlen) {
507	0	ERR_raise(ERR_LIB_EVP, EVP_R_MEMORY_LIMIT_EXCEEDED);
508	0	return 0;
509	0	}
510
511		/* Check that the maximum memory doesn't exceed a size_t limits */
512	0	if (maxmem > SIZE_MAX)
513	0	maxmem = SIZE_MAX;
514
515	0	if (Blen + Vlen > maxmem) {
516	0	ERR_raise(ERR_LIB_EVP, EVP_R_MEMORY_LIMIT_EXCEEDED);
517	0	return 0;
518	0	}
519
520		/* If no key return to indicate parameters are OK */
521	0	if (key == NULL)
522	0	return 1;
523
524	0	B = OPENSSL_malloc((size_t)(Blen + Vlen));
525	0	if (B == NULL)
526	0	return 0;
527	0	X = (uint32_t *)(B + Blen);
528	0	T = X + 32 * r;
529	0	V = T + 32 * r;
530	0	if (ossl_pkcs5_pbkdf2_hmac_ex(pass, passlen, salt, saltlen, 1, sha256,
531	0	(int)Blen, B, libctx, propq) == 0)
532	0	goto err;
533
534	0	for (i = 0; i < p; i++)
535	0	scryptROMix(B + 128 * r * i, r, N, X, T, V);
536
537	0	if (ossl_pkcs5_pbkdf2_hmac_ex(pass, passlen, B, (int)Blen, 1, sha256,
538	0	keylen, key, libctx, propq) == 0)
539	0	goto err;
540	0	rv = 1;
541	0	err:
542	0	if (rv == 0)
543	0	ERR_raise(ERR_LIB_EVP, EVP_R_PBKDF2_ERROR);
544
545	0	OPENSSL_clear_free(B, (size_t)(Blen + Vlen));
546	0	return rv;
547	0	}
548
549		#endif